It is well known that a silver halide color photographic material contains so-called dye-forming couplers (hereinafter simply referred to as "couplers") which form yellow, magenta and cyan dyes by a coupling reaction with an oxidation product of an aromatic primary amine developing agent to produce a color image.
Principles of color photography using couplers and general examples of couplers are described, for example, in T.H. James, The Theory of the Photographic Process, 4th Ed., Chap. 12 (published by Macmillan Co., 1977) and Research Disclosure, Item No. 17643 (December, 1978).
The above-mentioned publications disclose that phenols and naphthols have heretofore been used as cyan couplers.
However, cyan images to be formed from such conventional phenol and naphthol cyan couplers have a significant problem color reproducibility. The problem of cyan dyes produced from conventional phenol and naphthol cyan couplers occurs due to the poor toe sharpness in the short-wave side absorption so that the cyan dyes have an unnecessary absorption in the green range. In addition, since cyan dyes have an asymmetric absorption also in the blue range, the color reproducibility of the couplers is worsened to an even greater extent. In order to improve color reproducibility, a technique of incorporating a pyrazoloazole cyan coupler into at least one red-sensitive silver halide emulsion layer of a photographic material is disclosed in JP-A-64-552 and 64-554. (The term "JP-A" as used herein mean an "unexamined published Japanese patent application".) However, it has been found that the couplers disclosed in these Japanese patent applications do not have sufficient color reproducibility, the couplers have a low coupling activity and the light-fastness of the cyan images formed from the couplers is poor. As a result, the illustrated cyan couplers are not practical for use.
Couplers as illustrated in U.S. Pat. No. 4,728,598 have a maximum absorption wavelength range of from 538 nm to 602 nm and have a broad absorption so that they also are not sufficient as cyan couplers.